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    <title>kernel</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>kernel</b> -  kernel, nullspace</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>W=kernel(A [,tol,[,flag])  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>A</b>
        </tt>: full real or complex matrix or real sparse matrix</li>
      <li>
        <tt>
          <b>flag</b>
        </tt>: character string <tt>
          <b>'svd'</b>
        </tt> (default) or <tt>
          <b>'qr'</b>
        </tt>
      </li>
      <li>
        <tt>
          <b>tol</b>
        </tt>: real number</li>
      <li>
        <tt>
          <b>W</b>
        </tt>: full column rank matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>W=kernel(A)</b>
      </tt> returns the kernel (nullspace) of <tt>
        <b>A</b>
      </tt>. If A has full column rank then an empty matrix [] is returned.</p>
    <p>
      <tt>
        <b>flag</b>
      </tt> and <tt>
        <b>tol</b>
      </tt> are optional parameters: <tt>
        <b>flag = 'qr'</b>
      </tt> 
    or <tt>
        <b>'svd'</b>
      </tt> (default is <tt>
        <b>'svd'</b>
      </tt>).</p>
    <p>
      <tt>
        <b>tol</b>
      </tt> = tolerance parameter (of order <tt>
        <b>%eps</b>
      </tt> as default value).</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

A=rand(3,1)*rand(1,3);
A*kernel(A)
A=sparse(A);
clean(A*kernel(A))
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="colcomp.htm">
        <tt>
          <b>colcomp</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="fullrf.htm">
        <tt>
          <b>fullrf</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="fullrfk.htm">
        <tt>
          <b>fullrfk</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="linsolve.htm">
        <tt>
          <b>linsolve</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Author</font>
    </h3>
    <p>F.D.;   </p>
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